Dust cleaner

ABSTRACT

A dust cleaner applied to a process chamber having a heat plate comprises a dust-collecting cabin and at least a vacuum pipe. The dust-collecting cabin comprising at least one dust-collecting opening and one vent is disposed above the heat plate, and the vacuum pipe is connected with the vent. The suction force generated in the vacuum pipe can draw away the particles on the heat plate through the dust-collecting opening of the cabin and drain them out of the process chamber through the vent and the vacuum pipe.

BACKGROUND OF THE INVENTION

(1) Field of the Invention

The invention relates to a dust cleaning device and more particularly to the device that can automatically clean a surface of a heat plate inside a process chamber.

(2) Description of the Prior Art

In manufacturing a liquid crystal display (LCD), the circuit pattern on a glass substrate of the LCD can be formed by repeatedly performing Photo Engraving Processes on the glass substrate.

Typically, the Photo Engraving Process is performed by cleaning the substrate, plastering the photoresist onto the substrate, pre-baking the substrate, exposing and developing the photoresist on the substrate, post-baking the substrate, and finally etching the photoresist to form a desired circuit pattern.

In the art, the photoresist is a sticky solution having a polymer dissolved in a solvent. That is why the pre-baking is necessary after plastering the photoresist to vaporize the solvent and so as to solidify the polymer. The film of the polymer formed after the plastering has well adhesion to the substrate surface.

After being developed, the photoresist is post-baked at a greater temperature than that in the pre-baking so as to remove the solvent and adhesive moisture. Thereby, the combination among molecules of the photoresist can be stronger, and the stability of the photoresist against heat as well as the adhesion of to the bottom material of the glass substrate can be increased so as to have the photoresist structure better to meet the following etching process.

FIG. 1A is a schematic diagram of a conventional baking machine 1 which has a plurality of photoresist process chambers 10 for containing the glass substrate. After the photoresist on the glass substrate is plastered or is developed, the substrate is sent into the photoresist process chamber 10 for baking.

FIG. 1B is a schematic diagram of the photoresist process chamber 10. The chamber 10 is equipped with a heat plate 11 at the bottom and two covers 12 a, 12 b in the front side and the up side, respectively. The glass substrate 13 is sent into the chamber 10 through the front cover 12 a for a later baking process.

In the baking process, the upper surface of the heat plate 11 is gradually polluted by the dusts which may come from the photoresist or any in the working space. If the dusts are not removed, they may pollute the photoresist layer on the substrate 13 and thus cause defects in the circuit pattern. Thus, it is essential to keep the heat plate 11 clean for achieving a satisfied baking yield.

FIG. 2A is a schematic diagram to show a prior cleaning techniques. To clean the machine, the photoresist process chamber 10 is retrieved partially from the baking machine 1 as shown for opening the upside cover 12 b of the chamber 10. Then, a worker can utilize a vacuum machine 16 to vacuum the dusts on the heat plate 11 or he/she can wipe the. dusts off with a clean cloth moistened with alcohol.

However, as the size of the glass substrate increases, the heat plate for baking the substrate is also enlarged, and so is the volume of the baking machine.

FIG. 2B shows schematically how a worker cleans the chamber 10 having the cover 12 b open. As illustrated, the baking machine is at a height of H1, the height of the ladder is H2, the height of the worker is H3, and the width of the heat plate 11 is L1.

For a baking machine with a height of 3.3 m (H1), a worker having a height of 1.7 m (H3) would need a ladder of at least 1.6 m (H1) to execute thoroughly the cleaning process to have the upper heat plate 11 of the baking machine as shown in FIG. 2B to be cleaned. In particular for cleaning every position of the heat plate, he/she may have to bow down to clean with the result that the ladder needs to have a height higher than 1.6 m so that the H2+H3 can be greater than H1.

Moreover, the width of the big-scale heat plate may be about 2 m (L1), which the scale is usually larger than the height of a general worker. Therefore, the task to clean a big-scale heat plate is divided into two steps; one step to clean one half of the heat plate and another step to clean another half. Definitely, such a two-step cleaning would waste a lot of time. Besides, bowing down under the cover 12 b to clean the heat plate 11 may also bring unexpected risk to the worker.

In addition, there are still following shortcomings in the aforesaid cleaning:

-   -   1. The worker is allowed to execute the cleaning process only         when the temperature of the heat plate is cooled down from         130° C. (the working temperature) to at least 40° C. Such a long         period of time for cooling results in a bad producing         efficiency.     -   2. Due to the limitation in height and angle of a human         cleaning, possible blind corners for cleaning may arise and also         the worker may form a second pollution source. These reasons         results in a bad cleaning efficiency, increases the possibility         of a secondary pollution, and decreases the yield of baking the         photoresist.

Accordingly, any effort devoted to improving the cleaning techniques upon the heat plates of the baking machine so as to promote the efficiency and safety is definitely welcome to all the persons in the art.

SUMMARY OF THE INVENTION

One objective of the invention is to provide a dust cleaner applied to a process chamber of a baking machine so as to clean the heat plate's surface automatically.

Another objective of the invention is to provide a dust cleaner applied to a process chamber that can increase the efficiency in cleaning the heat plate's surface.

For those purposes, the mentioned dust cleaner applied to a process chamber with a heat plate comprises a dust-collecting cabin and at least one vacuum pipe.

The cabin disposed above the heat plate further comprises at least one dust-collecting opening and one vent. The shape and the size of the cabin can be designed according to the need. Since the process chamber is always operated under a high-temperature surrounding, the cabin can be made of heat-resistant material, like metal, pottery and etc.

The vacuum pipe is connected with the vent of the cabin and can be mounted across the process chamber by two guiding structures located at respective sides of the process chamber. The guiding structure can be formed as a slide track, a directive stick, or any equivalent structure that can fit the cabin and can utilize a driver to drive the cabin in a predetermined guiding route. Because the cabin moves frequently, and it is often operated in a wide temperature range so that the winding vacuum pipe shall experience expansion and shrinkage. For that reason, the vacuum pipe is made to be flexible against possible cracks on the pipe in a preferred case.

In the service of the baking machine, the surface of the heat plate will be polluted gradually. While cleaning is necessary, a suction force in the vacuum pipe will draw away the particles on the heat plate through the dust-collecting opening of the cabin, the particles will be drained out of the process chamber through the vent and the vacuum pipe, and at the same time the cabin can be moved by a driver for altering the vacuum area inside the cabin so as to thoroughly clean the heat plate as well as the interior of the cabin.

In addition, although one vent connected with one vacuum pipe is sufficient to provide the cabin suction force to draw away the particles, as mentioned above, the number of the vents and the vacuum pipes still can be changed according to different designs to meet different needs. For example, in a embodiment, there are two vents formed at two opposing ends of the cabin connected with vacuum pipes respectively.

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1A is a schematic diagram of a conventional baking machine.

FIG. 1B is a schematic diagram of a photoresist process chamber of FIG. 1A.

FIG. 2A is a perspective view of an opened process chamber of FIG. 1B to be cleaned.

FIG. 2B is a schematic diagram to show a conventional big-scale baking machine and a worker at cleaning one of the process chamber.

FIG. 3A is a perspective view of a first embodiment of the dust cleaner according to the present invention in a process chamber with part of the top cover removed for better showing the dust cleaner thereinside.

FIG. 3B is a cross sectional view of the cabin of FIG. 3A along line a-a.

FIG. 3C is another cross sectional view of the cabin of FIG. 3A along line b-b.

FIG. 4A is a perspective view of a second embodiment of the dust cleaner according to the present invention in a process chamber with part of the top cover removed for better showing the dust cleaner thereinside.

FIG. 4B is a cross sectional view of the cabin of FIG. 4A along line c-c.

DESCRIPTION OF THE PREFERRED EMBODIMENTS

The invention disclosed herein is directed to a dust cleaner applied to a process chamber. In the following description, numerous details are set forth in order to provide a thorough understanding of the present invention. It will be appreciated by one skilled in the art that variations of these specific details are possible while still achieving the results of the present invention. In other instance, well-known components are not described in detail in order not to unnecessarily obscure the present invention.

Referring now to FIGS. 3A and 3B, a perspective of a first embodiment of the dust cleaner applied to a process chamber and a cross sectional view showing its cabin 21 a along line a-a are shown, respectively.

The dust cleaner is constructed in a photoresist process chamber 10 which comprises a housing 101 and a heat plate 11 disposed on the bottom of the housing 101 to heat the air and bake the photoresist on a substrate.

The dust cleaner comprises a dust-collecting cabin 21 a, two vacuum pipes 22, a guiding structure 23, and a driver 24. The cabin 21 a located above the heat plate 11 is made of metal and is profiled as a hollow cylinder with a slit longitudinal dust-collecting opening 211 facing the heat plate 11 and at least one vent 212 formed at one end of the cabin 21 a (two vents 212 formed at two opposing ends shown in the figure).

As shown, Each of the vacuum pipes 22 is connected to the respective vent 212 at the end of the cabin 21 a. The vacuum pipe 22 is flexible and provides the suction force, or say the vacuum force, while in cleaning. In addition, an electromagnetic valve or an equivalent switch (not shown in the figures) can be constructed along with the vacuum pipe 22 to control on/off of the vacuum pipe 22.

The guiding structure 23 includes two slide slots 23 a and 23 b located respectively at two opposing sides of the photoresist process chamber 10 and sliding engaged with respective ends of the dust-collecting. cabin 21 a.

The driver 24, located at one end of the dust-collecting cabin 21 a, is guided by the guiding structure 23 to drive the cabin 21 a as well as the vacuum pipe 22 moving along the X direction as shown in FIG. 3A.

In the photoresist baking process, the surface of the heat plate is gradually polluted by particles 14. As shown in FIG. 3C, while a cleaning is necessary, the suction force in the vacuum pipes 22 will draw away the particles 14 on the heat plate 11 through the dust-collecting opening 211 of the cabin 21 a, and drain them out of the process chamber 10 through the vents 212 and the vacuum pipes 22. While in cleaning, the driver 24 can drive the cabin 21 a at a predetermined route to slide along the slide slots 23 a and 23 b so as to have the dust-collecting opening 211 screen over the heat plate 11 for achieving a better cleaning performance.

Obviously, the particles can be drawn in the similar way while there is only one vent formed at one end of the cabin and connected with one pipe in else embodiments of the present invention. Therefore, this is not illustrated in detail again for the sake of brevity.

Please referring to FIG. 4A, it is a perspective view of a second embodiment of the dust cleaner in accordance with the invention.

Compared to the first embodiment shown in FIG. 3A, this embodiment includes almost the same elements as the first embodiment does. Yet, a significant difference is that the dust-collecting cabin 21 b of the second embodiment is constructed as a slab cabin whose bottom surface has about the same area as the upper surface of the heat plate 11 has. The slab cabin 21 b includes a plurality of dust-collecting openings 211 facing the heat plate 11 and two vents 212 at two opposing sides.

As shown in FIG. 4B, while a cleaning is necessary, the suction force in the vacuum pipes 22 will draw away particles 14 on the heat plate 11 through the dust-collecting openings 211 of the cabin 21 b, and drain them out of the process chamber 10 through the vents 212 and the vacuum pipes 22.

Since the bottom surface of the dust-collecting cabin 21 has almost the same area as the upper surface of the heat plate 11, the particles at any spot of the upper surface of the heat plate 11 can be easily drawn away without moving the cabin 21 b.

It is clear the invented dust cleaner applied to the process chamber has various advantages at least as follows:

-   -   1. By providing the invented dust cleaner applied to the process         chamber, workers as well as the ladder for on-site cleaning the         chamber of the baking machine are no longer needed so that risk         to the workers can be reduced.     -   2. By providing the invented dust cleaner applied to the process         chamber, uncovering the process chamber for cleaning and waiting         for the heat plate to cool down to room temperature is no more         required so that labors and time for cleaning can be         substantially saved and production efficiency of the photoresist         process chamber can also be enhanced.     -   3. By providing the invented dust cleaner applied to the process         chamber, the particles on the heat plate can be removed out of         the chamber easily and thoroughly. Besides, compared with the         prior art, the time for cleaning is much shorter so that the         photoresist process chamber can be cleaned at any available         time.

The embodiment above is to illustrate the invention in detail but not to give a specific embodiment. Any modification that doesn't exceed the essence of the invention should belong to this invention. Thus the invention should be safeguarded according to the claims as follows. 

1. A dust cleaner for a process chamber including a heat plate, comprising: a dust-collecting cabin, located above the heat plate, having at least one dust-collecting opening and a vent; and at least one vacuum pipe connected to the vent of the dust-collecting cabin.
 2. The dust cleaner of claim 1, wherein said dust-collecting opening is a slit.
 3. The dust cleaner of claim 1, wherein said dust-collecting cabin is a slab.
 4. The dust cleaner of claim 1, wherein said vacuum pipe is made of a flexible material.
 5. The dust cleaner of claim 1, wherein said dust-collecting cabin is made of a heat-resistant material.
 6. A process chamber, comprising: a housing; a heat plate, disposed on the bottom of the housing; a dust-collecting cabin, located above the heat plate, including at least one dust-collecting opening and a vent; and at least one vacuum pipe connected to the vent of the dust-collecting cabin.
 7. The process chamber according to claim 6, further including: a guiding structure, having two slide slots for two opposing ends of the dust-collecting cabin to slide there along; and a driver for driving the cabin to move along the slide slots.
 8. The process chamber according to claim 6, wherein said dust-collecting opening is a slit.
 9. The process chamber according to claim 6, wherein said dust-collecting cabin is a slab.
 10. The process chamber according to claim 6, wherein said vacuum pipe is made of a flexible material.
 11. The process chamber according to claim 6, wherein said dust-collecting cabin is made of a heat-resistant material. 